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Present and Future Wind Energy Resources in Western CanadaDaines, Jeffrey Thomas 17 September 2015 (has links)
Wind power presently plays a minor role in Western Canada as compared to
hydroelectric power in British Columbia and coal and natural gas thermal power generation in Alberta. However, ongoing reductions in the cost of wind power generation
facilities and the increasing costs of conventional power generation, particularly if the
cost to the environment is included, suggest that assessment of the present and future
wind field in Western Canada is of some importance.
To assess present wind power, raw hourly wind speeds and homogenized monthly
mean wind speeds from 30 stations in Western Canada were analyzed over the period
1971-2000 (past). The hourly data were adjusted using the homogenized monthly
means to attempt to compensate for differences in anemometer height from the standard
height of 10m and changes in observing equipment at stations.
A regional reanalysis product, the North American Regional Reanalysis (NARR),
and simulations conducted with the Canadian Regional Climate Model (CRCM)
driven with global reanalysis boundary forcing, were compared to the adjusted station
wind-speed time-series and probability distributions. The NARR had a better temporal
correlation with the observations, than the CRCM. We posit this is due to the NARR assimilating regional observations, whereas the
CRCM did not. The NARR was generally worse than the CRCM in reproducing the observed speed distribution, possibly due to the crude representation of the regional
topography in NARR. While the CRCM was run at both standard (45 km) and
fine (15 km) resolution, the fine grid spacing does not always provide better results:
the character of the surrounding topography appears to be an important factor for
determining the level of agreement.
Multiple simulations of the CRCM at the 45 km resolution were also driven by
two global climate models (GCMs) over the periods 1971-2000 (using only historic
emissions) and 2031-2060 (using the A2 emissions scenario). In light of the CRCM
biases relative to the observations, these simulations were calibrated using quantile-quantile matching to the adjusted station observations to obtain ensembles of 9 and
25 projected wind speed distributions for the 2031-2060 period (future) at the station
locations. Both bias correction and change factor techniques were used for calibration.
At most station locations modest increases in mean wind speed were found for most
of the projected distributions, but with a large variance.
Estimates of wind power density for the projected speed distributions were made
using a relationship between wind speed and power from a CRCM simulation for both
time periods using the 15km grid. As would be expected from the wind speed results
and the proportionality of wind power to the cube of wind speed, wind power at the
station locations is more likely than not to increase in the 2031-2060 period from the
1971-2000 period.
Relative changes in mean wind speeds at station locations were found to be insensitive
to the station observations and choice of calibration technique, suggesting
that we estimate relative change at all 45km grid points using all pairs of past/future
mean wind speeds from the CRCM simulations. Overall, our results suggest that
wind energy resources in Western Canada are reasonably likely to increase at least
modestly in the future. / Graduate / 0725 / 0608 / jtdaines@uvic.ca
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On antarctic wind engineeringSanz Rodrigo, Javier 18 March 2011 (has links)
Antarctic Wind Engineering deals with the effects of wind on the built environment. The assessment of wind induced forces, wind resource and wind driven snowdrifts are the main tasks for a wind engineer when participating on the design of an Antarctic building. While conventional Wind Engineering techniques are generally applicable to the Antarctic environment, there are some aspects that require further analysis due to the special characteristics of the Antarctic wind climate and its boundary layer meteorology. <p>The first issue in remote places like Antarctica is the lack of site wind measurements and meteorological information in general. In order to complement this shortage of information various meteorological databases have been surveyed. Global Reanalyses, produced by the European Met Office ECMWF, and RACMO/ANT mesoscale model simulations, produced by the Institute for Marine and Atmospheric Research of Utrecht University (IMAU), have been validated versus independent observations from a network of 115 automatic weather stations. The resolution of these models, of some tens of kilometers, is sufficient to characterize the wind climate in areas of smooth topography like the interior plateaus or the coastal ice shelves. In contrast, in escarpment and coastal areas, where the terrain gets rugged and katabatic winds are further intensified in confluence zones, the models lack resolution and underestimate the wind velocity. <p>The Antarctic atmospheric boundary layer (ABL) is characterized by the presence of strong katabatic winds that are generated by the presence of surface temperature inversions in sloping terrain. This inversion is persistent in Antarctica due to an almost continuous cooling by longwave radiation, especially during the winter night. As a result, the ABL is stably stratified most of the time and, only when the wind speed is high it becomes near neutrally stratified. This thesis also aims at making a critical review of the hypothesis underlying wind engineering models when extreme boundary layer situations are faced. It will be shown that the classical approach of assuming a neutral log-law in the surface layer can hold for studies of wind loading under strong winds but can be of limited use when detailed assessments are pursued. <p>The Antarctic landscape, mostly composed of very long fetches of ice covered terrain, makes it an optimum natural laboratory for the development of homogeneous boundary layers, which are a basic need for the formulation of ABL theories. Flux-profile measurements, made at Halley Research Station in the Brunt Ice Shelf by the British Antarctic Survery (BAS), have been used to analyze boundary layer similarity in view of formulating a one-dimensional ABL model. A 1D model of the neutral and stable boundary layer with a transport model for blowing snow has been implemented and verified versus test cases of the literature. A validation of quasi-stationary homogeneous profiles at different levels of stability confirms that such 1D models can be used to classify wind profiles to be used as boundary conditions for detailed 3D computational wind engineering studies. <p>A summary of the wind engineering activities carried out during the design of the Antarctic Research Station is provided as contextual reference and point of departure of this thesis. An elevated building on top of sloping terrain and connected to an under-snow garage constitutes a challenging environment for building design. Building aerodynamics and snowdrift management were tested in the von Karman Institute L1B wind tunnel for different building geometries and ridge integrations. Not only for safety and cost reduction but also for the integration of renewable energies, important benefits in the design of a building can be achieved if wind engineering is considered since the conceptual phase of the integrated building design process.<p> / Doctorat en Sciences de l'ingénieur / info:eu-repo/semantics/nonPublished
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